Fibrous materials such as straw from flax, sisal, hemp, jute and coir, banana among others, consist of four main compounds: cellulose, hemicellulose, lignin, and impurities (e.g., dirt, dust). When these fibrous materials are used in the formation of biocomposite materials, it is the cellulose component of the fibrous material that contains and provides the strength and structural properties that are desired, while the hemicellulose, lignin, and the impurities have no real value for the biocomposite material in terms of properties or performance enhancements. As a result, these components of the fibrous material are removed prior to use in the formation of biocomposite materials.
One method in which the cellulose is removed from the remainder of the fraction is by pretreatment and washing the fibrous material. Current washing practices are able to remove the maximum amount of hemicellulose and impurities from the fibrous materials. However, these washing techniques have problems removing the lignin from the fibers, which necessitates additional processing of the fibers in order to remove the lignin, which is undesirable for use in the formulation of biocomposite materials for various reasons.
As a result, it is desirable to develop a mechanism and method that can overcome the deficiencies of prior art washing methods to remove the maximum amount of unwanted compounds from fibrous materials, e.g., the hemicellulose and lignin fractions along with the impurities that may be present, while leaving the cellulose undamaged to maximize the benefits provided to the biocomposite material including the cellulose. In particular, such a mechanism will maximize the strength characteristics of the fiber by leaving the cellulose fraction undamaged. The mechanism must additionally be formed of materials that are resistant to corrosion (i.e. plastic, stainless steel), as the washing agents utilized in the method can be corrosive.